A wide variety of content is currently available in digital form, such as articles, papers, other publications, images, video, audio, combinations thereof, etc. As digital content has become increasingly popular, mechanisms have been developed to allow actions normally associated with content in more traditional forms (e.g., paper) to be performed on digital content. An example of such is the annotation of content. A reader of a traditional paper-copy of an article is able to use a pen or pencil to jot down notes in the margins, underline or circle sections of the article, use a highlighter to highlight portions of the article, etc. Systems are being developed that allow such actions to be performed on digital forms of content as well.
Annotating of digital content can provide numerous benefits, such as allowing multiple individuals to view (or hear) and annotate the content concurrently. However, one problem faced with annotating such digital content is how users are made aware of the annotations. One solution is to require the user to re-view the content in order to view the annotations, however this is burdensome on the part of the user. Another solution is for the annotation author to send an electronic mail (email) message to a certain user(s) whenever he or she adds a new annotation to the document. However, this is also burdensome on the user as it requires the annotation author to identify the user(s) to receive the electronic mail messages, and can result in numerous electronic mail messages being sent to the user. Thus, improvements are needed in how users are made aware of annotations.
Digital content also allows certain actions to be taken that cannot be easily taken with non-digital content. For example, content can be more easily edited by multiple persons, and can even be edited by multiple persons concurrently. However, as with annotating content, there is a problem faced in how users are notified of changes to the content.
Notification of activity around documents described herein helps solve these and other problems.